After the storm-swollen Scuppernong River nearly drowned Columbia, N.C., last year, town leaders were convinced that their waterside hamlet had become dangerously low. So they passed a measure requiring new buildings to be 2 feet higher.

It's an aggressive standard that eclipses many local height requirements in North Carolina, but it sailed through the Board of Aldermen with barely a crosswind. The easy sell came three months after Hurricane Irene wheeled onto the wooded shoreline near Columbia, driving a surge of seawater down the river's throat and through the small town.

That provided all the proof that elected officials needed. Townspeople had watched the water rise until it soaked into roughly 80 percent of Columbia's buildings, said town Manager Rhett White, who called the 2-foot standard "a fairly easy recommendation." It passed unanimously.

The case in Columbia seems to strike a winning argument for climate adaptation, but it started a storm of its own. State lawmakers appear poised to prevent similar policies, as comedian Stephen Colbert derisively put it, by passing legislation that makes sea-level rise illegal. The Legislature is considering a bill to stop local and state land-use standards from incorporating scientific projections of accelerated sea-level rise -- one basis for building structures higher.

The decision in Columbia to protect the town from storm-prone flooding shows that the reasons provided for adopting a policy can become more controversial than the regulation itself.

"Sea-level rise as such was not mentioned. It was not a part of the consideration," White said of the board's approval of higher elevation standards. If it were, "I don't think it would have even been considered."

North Carolina is no stranger to policies that restrict coastal development. It makes builders consider local erosion rates; the more shore that's lost annually, the farther back a house must be built from the water. And at last count, nearly half the state's 112 coastal communities had standards requiring structures to be built at least 2 feet above federally designated flood levels. Columbia jumped to 3 feet with its new policy.

But the natural forces spurring those policies tend to be hazards that people can see. Beach sands are surrendering to waves and storms, often at a visible pace. Hurricanes lash homes with wind and rain from above, while flooding them from below.

Rising oceans a 'very poor' argument
So to some, the Legislature's negative reaction to a proposal by the state's Coastal Resources Commission advising that land-use standards should incorporate 39 inches of sea-level rise by 2100 isn't surprising. The bill, which a Senate committee unanimously passed Thursday, says communities should consider only historical trends of sea-level rise, which might amount to 8 inches by 2100.

"Part of the problem is that sea-level rise is a very poor tool to justify immediate action in almost any way," said Spencer Rogers, an engineer who studies coastal construction for North Carolina Sea Grant, which is partly funded by the National Oceanic and Atmospheric Administration. "The question is, what's the best reasoning to do that? It's often not sea-level rise and climate."

The long timeline associated with rising seas is one problem. But the state policy debate has also become mired in the national politics around climate change. The coastal commission's report, which came out in 2010, has been intensely criticized by NC-20, a group of economic developers and political activists representing the state's 20 coastal counties.

The group's chairman, Tom Thompson, says he doesn't trust mainstream climate scientists who say that greenhouse gases emitted by human activities could have a substantial effect on things like rising seas. He argues that climate change is similar to a previous fascination with "global cooling," even though the scientific research on the impacts of greenhouse gases is far more robust.

"Carbon dioxide is 0.039 percent -- that's it -- of the Earth's atmosphere," said Thompson, the economic development director for Beaufort County, N.C. "To suggest that's having an enormous influence on the Earth's climate is almost, you know, it's farcical almost."

He added: "CO2 is actually good for the Earth. And that's why we have, again, such prolific plant growth today and things like that. We've plotted CO2 since the [1930s] against sea-level rise. There's no correlation. Zero correlation. They do not correlate."

Benchmark melts in warming debate
Scientists disagree. NC-20 is focusing its criticism on the idea that sea-level rise could accelerate by about 2030, when scientists say higher temperatures will expand ocean water while increasingly melting ice found in Greenland and Antarctica.

Orrin Pilkey, an expert on sea-level rise and an emeritus professor at Duke University, warned that the projected rate of rise is "very clear and very ominous" in an op-ed in the News & Observer last week.

The acceleration is expected to be caused in part by the melting from warmer air, he said. But climbing water temperatures might have a bigger impact: That could destabilize some of the 50 floating ice shelves ringing the edge of Antarctica; these shelves, the largest of which are the size of Texas, are holding back land-based glaciers that could also slip into the Antarctic Ocean.

"Their breakup will have an immediate and large effect on sea-level rise," Pilkey said of the ice shelves.

So far, however, NC-20's criticisms appear to be winning the debate. The Coastal Resources Commission, which is responsible for the state's coastal development policies, heavily edited its policy proposing a "planning benchmark" of 39 inches of sea-level rise by 2100. Now, the new document only encourages coastline communities to consider the rise in their land-use plans.

"The best I can determine, there was concern with the 39 inches even being out there -- being talked about," the commission's chairman, Bob Emory, said of NC-20's protests.

Emory said the commission was never interested in mandating new regulations for communities, which critics say potentially could have seen valuable property become unusable under an ambitious sea-level policy.

But others accuse the commission of forsaking science, or at least public policy, in the heat of the political moment. The commission's 2010 report was drafted by its science panel, a voluntary collection of geologists, engineers and others in North Carolina.

"They decided to sort of kick the ball down road, and they decided to 'educate' the public about sea-level rise, whatever that means, rather than encourage long-term planning," Rob Young, a geologist at Western Carolina University and a member of the science panel, said of the commission. He expressed disappointment that state officials are "essentially going to ignore the recommendations in the report."

Where's the incentive?
After the commission edited its policy proposal, state lawmakers introduced a bill that would ensure that towns, counties and the Coastal Resources Commission don't consider accelerated rates of sea-level rise. The bill, introduced by Republican state Sen. David Rouzer, instructs planners to account for rising seas based on historical data, rather than the potential accelerating rise generated from melting ice shelves and glaciers.

"It's as if the sea-level rise skeptics in North Carolina can't take yes for an answer," Young said. "The fact that the [coastal commission] decided not to regulate sea-level rise wasn't enough for them. They needed to have the Legislature codify a nonscientific sea-level rise policy for the state."

But Young acknowledged that perhaps the commission and the state Division of Coastal Management, which would implement the new rules, "probably went a little bit too fast with this from a political perspective."

Rudi Rudolph, a shoreline specialist with Carteret County, said the commission's proposal came across as heavy-handed. Rudolph, who believes that climate change is causing sea-level rise, wants an incentive-based approach to encourage smarter coastal construction. He notes that the National Flood Insurance Program gives discounts to policyholders who elevate their homes.

"If somebody tells you or me to buy a Prius because it's good for the environment, most people are going to go, 'Well, screw you,'" Rudolph said. "Now, if gas is at $7 a gallon, guess what I'm buying? A Prius."

Rouzer, the state senator, expects his bill to be passed by the chamber, perhaps this week, according to local news accounts. His office declined an interview request.

There are concerns that if the legislation passes, it might cloud the traditional role that hardening homes has played along the storm-battered coast. Some advocates wonder whether policies that were justified by hurricane flooding, like those in Columbia, could fall into disfavor by their association with climate change.

White, the town manager of Columbia, says he is "very concerned" about the legislation.

"The fact that it could be tied to something that's controversial like sea-level rise ... if that had the effect of preventing a community from addressing what they see to be a very real problem, then we certainly would be concerned about that," he said.

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